Solutions: Reusing Keurig K-Cups

We have switched over to one cup at a time coffee with the Mr. Coffee Keurig reconditioned model, which I bought pretty cheap. I get 80 k-cups for $25 at Costco, which is the cheapest I can find. I reuse my k-cups by plopping them into my plant watering container to give my plants extra nourishment when I water them. Just a couple of ways I have saved a bit when I made the decision to regulate our coffee drinking. If I want decaf I can fill the little k-cup holder with ground coffee of my own. I sprinkle those used grounds in the garden!

I love my Keurig coffee maker and the mess-less perfect cups of coffee they make but I have a problem throwing away all those empty little cups. I have begun using the cups to start seedlings for my spring garden. I remove the foil tops. The coffee maker has already punched a hole in the bottom of the cup! Rinse them out. Fill with soil, add seeds, keep moist and cover loosely in sunless area until seedlings appear and develop, as usual.

Questions

I love my Keurig coffee pot, but I tend to use quite a lot of the K-cups and they are not recyclable. I do clean them and re-use with some plastic K-caps I found on line. But after a few uses, the filter tears up and can't be used again. One suggestion is to use them for seed starters. I was wondering if anyone else has come up with uses for the empty cleaned K-cups.